This invention relates generally to a formulation that minimizes mixed inorganic deposits in non-phosphate or low-phosphate automatic dishwashing systems.
Automatic dishwashing detergents are generally recognized as a class of detergent compositions distinct from those used for fabric washing or water treatment. Automatic dishwashing detergents are required to produce a spotless and film-free appearance on washed items after a complete cleaning cycle. Phosphate-free or low-phosphate compositions rely on non-phosphate builders, such as salts of citrate, carbonate, silicate, disilicate, bicarbonate, aminocarboxylates and others to sequester calcium and magnesium from hard water, and upon drying, can leave an insoluble visible deposit. Polymers made from (meth)acrylic acid and maleic acid are known for use in inhibiting the scale or other insoluble deposits produced from non-phosphate builders. For example, WO 2009/123322 discloses polymers made from acrylic acid, maleic acid and a sulfonated monomer in a composition containing biodegradable builders. However, this reference does not disclose a composition containing a polymer with a lactone end group.
The problem addressed by this invention is to find a composition capable of reducing formation of mixed inorganic deposits.